Neon-tube.



G.4 CLAUDE.

NEON T-uBE.-

APPLICATION FILED JUNE I5, I9I5.

LQMAQL 'Patented June 26, 1917.

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Specification of Letters Patent.

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E .EoUEoenE'sUE-SEINE, FRANCE.

NEON-TUBE. i i

Patented June 26, 1911"?.

- Application led .Tune 16, 1915. Serial No. 34,555.

lTo all wkom it may concern.

` Aquently renders them Be it'4 known that I, citizen of the Republic at Boulogne-sur-Seine, vented certain new and v-of France, residing France, have 1nuseful- Improvements in Neon-Tubes, of which the-following is a specification. t. v t

The-present mventlon relates to improveinents in neon tubes for lighting purposes, A.and it' aims ,primarily to overcome a defect tubes when emand which freincapable ofuse without their light being correctedin some way, owing to the excessive amount of red contained therein. 'l v 'It hasl been proposed to eil'ect such correcwhich is inherent in neon ployedf for this purpose,

v tion by means' of light suppliedA by mercury tubes, which emit too little red light and too much lgreen or violet light, but this has proven unsatisfactory for the reason that the ordinary -mercury vapor tubes 'are vworked by low-pressure continuouscurrent,

require high-pressure whereas neon tubes alternating current. i Y, t t .l

According to `the present invention, the requisite correction is -.obtained` by introducing a few drops of 4mercury intov a neontube and then passing an alternating current therethrough in the manner usual with neon tubes, the heat generated by the lcurrent soon volatilizing .the mercury, the n vaporv of, which fills the entire tube, while the neon radiations completely` disappear. The radiations of the .corrector tube, thus formed, are then added to the red 'radiations Of an adjoining' neon tube, giving la greatly improved resultant light. lt is ob- 'Vention; t i AVi Figs/e 2.5",13 and i4 show,

vious, though, that 1n order to make the correction as light ofthe neon tube, hereinafter termed the red' tube, and the *blue light of the neon and mercury blue or corrector tube, must be suitably prored tube and the blue corrector tube have the samediameter, and the same current is as the red tube to ,t obtain agood correction.

"Figure 1 shows one embodiment of the in- Fig.A 5 shows-a diagram of the wiring used.

GrEoRGEsl CLAUDE, a

lof the corrector tube and the perfect as possible, the redV tube, hereinafter termed the` I ,have shown that, portioned.- lt has been found thatl ifthe each, a separate v One arrangement which has proven satisfactory, consists in placing a straight neon tube A, (Fig. 1), between .the two branches of a U-shaped tube `B of the-samadiameter containing neon and mercury, and in passing the same current through both tubes; or in a generally similar manner, in interposing a neon tube between two blue tubes of practically the same length and of the same diameter, A'for instance an oval red tube A, (Fig. 2), between two blue `ovals B and C, the whole being connected-in series.

'This arrangement has, however, the drawback of being too expensive, since it requires. three adjoining tubes. Moreover, the color ofthe light supplied is generally not very satisfactory, approaching either mauve or aA verfy pronounced pink. It would also be ldesirable to makeA this correction of a red tube employed in the preceding arrangement.

It can be easily solved if the red tube and the blue or corrector tube are supplied separately with different currents, as it will obviously be possible to choose the' diameter current passlng through the same, in such a manner as to comply with the. desired condition. rlhe matter is more diiiicult when, the high voltage being produced by a 'transformer or by a Rumkorf coil, it `is advisable to supply the two tubes in series with the same current,.becaus'e in -that case, the supply in parallel from a single transformer is a delicate matter. f 4 t An excellent solution ofthe problem is obtained by bearing in mind the following considerations Series of very complete measurements rent, the fall of potential in the neon tubes, and in the neon and mercury. tubes, is inversely proportional to -the diameter, (Gammes Rendu-s de @Academie des Sciences, 1 September, 1913', Iand 16 Febru ary, 1914), and that, even with equal currents, the smaller the diameter of the tubes, the greater the voltage required by them. @ther measurements, (Uomptes Rendus, 9 March, 1914), have shown that the quantity of light supplied by thetubes in fquestion,

with equal density of curdiameter, it will be the smaller tube .that-` will supply the greater fquantity offlight,

.as that tube will consume'the greater quantity of energy, owing tothe extra voltage that it requires. And it has, in fact, been found that a tube of unit diameter supplies,

practically, twice as much lightas a`tube of twice the diameter through which-the same cui/rent .is passed.

replace the double length of blue corrector.

tube above referred to,`\by a single length B, (Figs. 3 'and 4), of a tube of a smaller diameter connected in series with the red tube A to be corrected andvpreferably -arranged very close to the latter. L

This arrangement has numerousadvantages. First,v it is obviously the simplest method of rectifying the light by corrector tubes. This Amethod is the best .not only' from the point of view of,economy, as thecorrector tube, being only of small diameter,`

is comparatively inexpensive, but also from the point of view of efficiency, las the v`constant loss at the electrodes is .smaller relatively to the total voltage ofthe small tube. It is also'preferable from the po,intof view offsafety, as the supply of the two tubes con'-J nected in series at one of their ends is effected through the other end, so thatfvit is-possible to do away with high-tension conducin -a more efficacious manner.

tors, if desired. Onthe other hand, experience shows that with'these blue tubestwith-` great current density the light supplied"is less pale and neutralizes the red of the -neon' Finally, the color of the light obtained can be varied with great-exactitude merely by varying the diameter of the corrector tube. .Thus ifthe diameter of the corrector tube is increased, the proportion of blue is reduced, while if thel saidfdiameter is reduced the proportion of blue is increased, and the light made more' mauve'. j

All these advantages are therefore consequences of the arrangement herein claimed and consisting in the combinatidnof a neon. l tube with aY neon-and mercury tube of prac;

tically the same length, the same current l passing throughboth, but'the latter tube producing a sufiicient' quantity of correcting lightcwing to its smaller diameter.

It is possible, for instance, to bbtain easily portable lighting sets by the combination of two similar tubes-of equal length, for instancev .6 m., arranged almost side` byside,4 .the inside diameter of theneon tube, however,- being 20 mm. while that of the nen and mercury .tube is only' l0 nim. These tubes may be straight, 'oreither oval or circular in shape, as preferred, and in the last two instances are disposed concentrically. y

that which't Yhowed at Thus, it is. possible to' iitial or red ight stage. Duringthe lighting vinserted vin the low pressure circuit. When lighting up, the neon in both tubes initially becomes luminescentfand it is only gradually that the blue A,or correeting light appears and develops, b'ut the luminous in` -'15' tensity of the neoniand mercury tube, when ,e its light has become blue,is much less thanv Vfirst during lthe in -L up',ftherefore, there. will be ia 'very great luminous intensity in red which-will quickly decrease as the'blue progresses which .will

conveywthe disagreeable impression that the light is being gradually extinguished. Moresingle'transformer.which is just'sui'licient l for normal working, and in short-circuiting the red ltubeyuntil the other tube emits blue light, by progressively vvarying the intensity or the'voltage at4 the'terminals, or by limiting the time" of the said shortcircuiting tov 1 a' suitable period. lMoreover, a suit'able-re-4 1(151 sistance or self-induction coil could be connected invseries to the blue tube during the shoiat-circuiting, for the 'purpose of avoiding anexcessive current. In that way, sufficient -`voltage willbe obtained for easily lighting up the blue tube, without producing an in- A jurious excess of lred light at the beginning, and as soon as the mercury appears, after a few seconds ,the short-circuit is automatically cut out and the red tube becomes easily lighted in itsturn, the voltage being nowsufficient owing to theldecrease Vof the difference ofpotentialrequired by the blue tube. v' Y This arrangementA is moreover applicable to combinations of three tubes .of the'same diameter .through which -passes,- the same current, as mentioned inthe foregoing. f

.A method of automatically, obtaining this.

' momentary short-circuiting yof the red tube 125 when lighting up, is, for instance as follows` (Flg' 5): .L v x. When the-switch inserted 1n the low-pres- .sure'circuit of the transformer is closed, the high-pressure current passes for a very short 130.

vthe action of the spring R,

time through the red `tube A, the blue tube B, the electro-magnet E and the coil C; thearmature F ofthe electro-magnet E is attracted, and the mercury contact G shortcircuits the tube A. The coil'C then heats and expands the core H which, after an interval during `Which the tube B becomes blue, engages the contact I, which short-circuits said magnet E. t The plunger contact G is then withdrawn from the mercury by and the tube A becomes operative I claim:

l. electric lamp comprising two neon tubes` of suitable shape, grouped together tubes of the same length, mounted in series 20 in the same high-tension circuit, one of said tubes containing a few drops of mercury and having a diameter half that of the other tube.

GEORGES CLAUDE.

In presence of- E. LEDRET, CHAS. P. PRESSLY.

In testimony whereof I aix my signature. 25 

